import datetime
def get_diff_days(pdate, days):
    pdate_obj = datetime.datetime.strptime(pdate, '%Y-%m-%d')
    time_gap = datetime.timedelta(days=days)
    pdate_result = pdate_obj - time_gap
    return pdate_result.strftime("%Y-%m-%d")

print(get_diff_days("2025-08-11", 1))
print(get_diff_days("2025-08-11", 5))
print(get_diff_days("2025-08-11", 63))